Multi-material printing in SimplyPrint: mapping and syncing your AMS, ACE or CFS

If your printer has a multi-material system - a Bambu Lab AMS, an Anycubic ACE / ACE Pro, a Creality CFS, an ELEGOO Canvas, a Flashforge IFS or the Snapmaker U1's four toolheads - SimplyPrint can map the colors in your file to the spools you have loaded, and keep the loaded spools in sync between the printer and your filament inventory. This guide explains how that works, what each system supports, and how to map a multi-color print before you start it.

In this guide

• What multi-material support does
• Compatibility: which system supports what
• Mapping a print to your loaded spools
• Printers with two nozzles
• Color matching and match confidence
• Syncing spools from the printer
• Material syncing settings
• Telling SimplyPrint which system you have
• Related articles

What multi-material support does

A multi-material system (we call it an "MMS") holds several spools and feeds them to the printer so a single print can use multiple colors or materials. SimplyPrint works with these systems in two ways:

• Mapping - when you start a print that uses more than one color, SimplyPrint matches each color slot in the file to one of the spools loaded on the printer, so the right spool prints the right part. You can let it auto-match or pick each spool yourself.
• Synchronizing - SimplyPrint reads the spools currently loaded in the system and keeps them lined up with your filament inventory, so the panel always shows what is actually in each slot. Depending on the hardware, it can also create or assign inventory spools automatically.

Both build on the filament manager, which is where your spools live.

Compatibility: which system supports what

Mapping and syncing depend on the multi-material system AND on which client connects the printer to SimplyPrint.

What the columns mean, and why the systems differ:

• Sync (reading the loaded spools into the panel) works for every system in the table except the QIDI Box - each reports its loaded material and color to SimplyPrint. Sync is not Bambu-only.
• Auto-create and auto-assign are the part that differs, because they need the system to report a unique per-spool ID (so SimplyPrint can tell one "black PLA" apart from another):
• • Bambu Lab AMS - the spool's RFID tag reports a unique ID, so both work.
  • Anycubic ACE, ELEGOO Canvas and Flashforge IFS - they send no per-spool ID, so material and color sync but SimplyPrint can't tie a slot to a specific inventory spool. This is the hardware, not a limit SimplyPrint imposes.
  • Creality CFS - by default the CFS sends no usable ID either, but when you write the CFS tag through SimplyPrint it embeds the spool's own ID, which the CFS reports back - so auto-assign puts that spool in the right slot. There is nothing to auto-create: the tag was written from a spool that is already in your inventory.
  • Snapmaker U1 - the U1 reads Snapmaker's own RFID spools and reports the tag's ID, so both work for those spools. Other spools sync material type and colour only.
  • Full detail: Automatic spool creation when syncing materials.
• Mapping - SimplyPrint shows the slot mapping when you start a print, and the client sends it to the printer with the print, so each color prints from the slot you mapped. This works for the AMS, ACE, CFS, Canvas, IFS and U1.
• Anycubic, Creality, ELEGOO, Flashforge and Snapmaker go through the SimplyPrint Client. If a Creality printer is instead connected through Moonraker, mapping and sync are not available - the SimplyPrint Client integration is what provides them.

Mapping a print to your loaded spools

When you start a print that uses more than one color, SimplyPrint shows a material mapping step. Each color used in the file gets a slot, and you assign a loaded spool to it.

1. Pick the file and the printer you want to print on.
2. SimplyPrint reads the colors in the file and the spools loaded on the printer.
3. For each file color, it suggests the closest loaded spool. A confident suggestion is filled in automatically.
4. Click any slot to change the spool, or to assign one that was not auto-matched.
5. Once every color is mapped, the print can start.

If a color cannot be matched to any loaded spool, that slot stays empty and the print is held until you map it. You will see a "Must select/map materials" note until everything is assigned.

Printers with two nozzles

On a two-nozzle printer such as the Bambu Lab H2D or H2C, each filament prints from the nozzle it was sliced for. The mapping step groups the file's filaments by nozzle and only offers slots that feed that nozzle. To use a slot on the other nozzle, re-slice the file with the filament assigned to that nozzle. See Choosing the left or right nozzle on a Bambu Lab H2D or H2C.

Color matching and match confidence

SimplyPrint matches by comparing the color in the file to the color of each loaded spool, and it grades how close the match is. A high-confidence color match can stand in for an exact material match, so an obvious "this red slot is your red PLA" pairing is filled in for you.

When you open a slot, each candidate spool shows whether it is a clean match or whether something differs - color, material type, or temperature. This lets you spot, for example, that the closest color is actually the wrong material type before you commit to it.

You can always override the suggestion. A spool you pick yourself is treated as a deliberate choice, even if its color is not the mathematically closest one.

Syncing spools from the printer

Multi-material systems report which spools are loaded. SimplyPrint uses that to keep the panel in step with the physical unit.

Next to the mapping step's title there is a Refresh spools button. Pressing it asks the printer for its current multi-material state and re-reads the loaded spools, then rebuilds the mapping against what is actually there now.

The refresh button appears when the printer is online, supports material sync, and you have permission to change filament. If you do not see it, check that the printer is connected through a client that supports sync (see the compatibility table above). For a Creality CFS, see Creality CFS: slots not syncing and the refresh button.

Material syncing settings

How SimplyPrint syncs is set per account under Settings > Printers > Material syncing. You choose one syncing direction:

• Sync material from printer to SimplyPrint - the printer is the source of truth; loaded spools flow into the panel.
• Sync material from SimplyPrint to printer - the panel is the source of truth; what you set in SimplyPrint is pushed to the printer.
• 2-way sync - the latest change wins, in either direction. This is the default.
• Disable material syncing - no automatic syncing.

When syncing from the printer (or 2-way), two extra options become available:

• Auto-create spools when syncing materials if possible - if the printer gives enough detail to identify exactly which spool is loaded, and it is one SimplyPrint has not seen before, it can be added to your inventory automatically. This uses data from the Open Filament Database.
• Auto-assign spools to printers when syncing materials if possible - if the printer reports a unique spool ID (such as an NFC tag ID), SimplyPrint matches it against your existing spools and assigns the match to the correct slot.

Whether auto-create and auto-assign actually fire depends on what the hardware reports. That is the heart of Automatic spool creation when syncing materials - read it for exactly when each system can and cannot do this.

Telling SimplyPrint which system you have

For most supported printers the multi-material system is already part of the printer model, or the SimplyPrint Client reads it from the printer, so there is nothing to set up. If you have added a system that is not detected automatically, or you have chained several units together, you can configure it on the printer.

In the printer's multi-material systems settings you can:

• add one or more systems for the nozzle (for example an AMS, a QIDI Box, or a custom unit),
• set how many units are chained together (up to 4 for the AMS, AMS 2 Pro, ACE Pro, ACE 2 Pro, CFS and QIDI Box),
• and, for a custom system, set how many slots it has.

Once the system is set, its slots show up in the control panel and in the mapping step, ready for spools to be loaded and mapped.

Related articles

• Automatic spool creation when syncing materials
• Choosing the left or right nozzle on a Bambu Lab H2D or H2C
• Creality CFS: slots not syncing and the refresh button
• Snapmaker U1: connecting it, toolheads and filament sync
• The filament manager: track, organize and manage your filament inventory
• All about NFC / RFID for filament spools
• The Creality material standard: NFC / RFID for the Creality CFS
• The ELEGOO material standard: NFC / RFID for the ELEGOO Canvas

Updated on: 27/10/2026